is a drilling rig
used in the petroleum industry
for offshore drilling
that is very similar to a drilling barge
but with three to four supporting legs. The jack-up gets transported to the drill site with its legs up. Once at the drill site, the legs, previously preloaded, are hydraullically jacked into place on the bottom of the ocean floor. The legs are pushed further down but because they have been preloaded, the jacking down of the legs also triggers a jacking mechanism attached to a triangular shaped platform and drilling package that simultaneously, jacks up the entire drilling platform to a predetermined height so it rests above the water. As a result of this "jacking" feature, a jack-up is much safer to operate than a drilling barge because only the rig's legs are in the path of ocean currents and waves and not the entire platform and drilling package.
- ↑ Jack-up. Schlumberger Oilfield Glossary. 26-05-2009.